1. Field of the Invention
This invention relates to a method of preventing deterioration of surfaces of inorganic substrates comprising cement, concrete, gypsum or mixtures thereof. The method can be applied to the surfaces of different types of buildings and construction made with said inorganic substrates to achieve uniformly excellent results in effectively protecting said surfaces from deterioration due to exposure to the elements.
2. Description of the Prior Art
Heretofore, cement, concrete, gypsum, etc. have been widely used in various fields such as in construction of buildings and other structures. Especially, spray coating of cement by the lithin process has been considered economical so that it has been subject to wide application in the outer surface finish coatings of concrete mortar. Since the thickness of a thus formed surface layer is thin, the unreacted calcium hydroxide component and the cement component have been found to deteriorate through a carbonation efflorescence so that the surface layer protection is progressively removed by a powdery deterioration within 1 or 2 years. Similar deterioration phenomena have been found to take place on processed surfaces of cement type mastic coats and gypsum coats. Cement type mastic coats have particular disadvantages in that cracking is common. Heretofore, no known attempt for preventing such deterioration has been successful.